<!DOCTYPE html>
<html>
<head>
    <title>欢迎页</title>
    <style>
        body { font-family: Arial, sans-serif; background: #f5f5f5; }
        .welcome-container { max-width: 400px; margin: 50px auto; padding: 20px; background: white; border-radius: 5px; box-shadow: 0 0 10px rgba(0,0,0,0.1); text-align: center; }
        .logout-btn { display: inline-block; margin-top: 20px; padding: 8px 15px; background: #f44336; color: white; text-decoration: none; border-radius: 4px; }
    </style>
</head>
<body>
    <div class="welcome-container">
        <h2>欢迎, {{ username }}!</h2>
        <p>您已成功登录系统</p>
        <a href="{{ url_for('logout') }}" class="logout-btn">退出登录</a>
    </div>
</body>
</html>